Differentialwiderstand

Differentialwiderstand, also known as dynamic resistance or incremental resistance, refers to the change in voltage across an electrical component divided by the corresponding change in current through it, at a specific operating point. It is a measure of how much the resistance of a component changes as the voltage or current varies. Mathematically, it is represented by the derivative of the voltage with respect to current, dV/dI.

This concept is particularly important for non-linear components, such as diodes and transistors, where the relationship between voltage and current is not constant. For a linear resistor, the differential resistance is equal to its static resistance (V/I) because the resistance is constant. However, for a diode, the differential resistance is typically much smaller than its static resistance, especially when the diode is forward-biased. This is because a small change in voltage can cause a large change in current.

Understanding differential resistance is crucial for analyzing the behavior of electronic circuits, especially in AC signal analysis and the design of amplifiers and oscillators. It helps predict how a circuit will respond to small signal variations around a DC bias point.